Apache error logs are dominated by PHP Warnings about ini_set():
[proxy_fcgi:error] [pid 155565:tid 139937995278080] [client 54.228.194.245:51803] AH01071: Got error 'PHP message: PHP Warning: ini_set(): Session ini settings cannot be changed when a session is active in /var/www/html/support/bootstrap.php on line 19PHP message: PHP Warning: session_cache_limiter(): Session cache limiter cannot be changed when a session is active in /var/www/html/support/bootstrap.php on line 21'
PHP error logs are part of the apache error logs. The MySQL database is on Amazon RDS, so the logs are not especially accessible. And the osticket logs don't seem to contain anything.
Logging in this morning yielded the above PHP error, then after a few minutes the screen reloaded to a blank ticket list, and the following error appeared in Apache's error log:
Got error 'PHP message: PHP Fatal error: Uncaught Error: The script tried to call a method on an incomplete object. Please ensure that the class definition "QueueSort" of the object you are trying to operate on was loaded before unserialize() gets called or provide an autoloader to load the class definition in /var/www/html/support/include/staff/templates/queue-tickets.tmpl.php:83\nStack trace:\n#0 /var/www/html/support/scp/tickets.php(561): require_once()\n#1 /var/www/html/support/scp/index.php(17): require('...')\n#2 {main}\n thrown in /var/www/html/support/include/staff/templates/queue-tickets.tmpl.php on line 83', referer: http://##.##.##/support/scp/index.php